http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54602
--- Comment #4 from Kazumoto Kojima <kkojima at gcc dot gnu.org> 2012-10-10 22:44:17 UTC --- (In reply to comment #3) > Kaz, could you please also have a pre-look at this? I might be missing > something... Looks reasonable to me, though I also might be missing something. > Also, I've noticed that on SH4 (which has banked regs R0..R7) the banked regs > are also saved / restored in an interrupt function. This actually defeats the > purpose of the R0..R7 register bank. Maybe some historic reason, or just > accident? I don't know the history about it. I can only imagine that some system could assume some banked regs will be not clobbered with their exception handler and will be used like as normal registers. A new -m option which controls the behavior of which default is not to save/restore the banked regs?
